[PATCH 5.9 214/252] iio/adc: ingenic: Fix battery VREF for JZ4770 SoC

[Greg Kroah-Hartman]

From: Paul Cercueil <paul@xxxxxxxxxxxxxxx>

commit c91ebcc578e09783cfa4d85c1b437790f140f29a upstream.

The reference voltage for the battery is clearly marked as 1.2V in the
programming manual. With this fixed, the battery channel now returns
correct values.

Fixes: a515d6488505 ("IIO: Ingenic JZ47xx: Add support for JZ4770 SoC ADC.")
Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx>
Acked-by: Artur Rojek <contact@xxxxxxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20201104192843.67187-1-paul@xxxxxxxxxxxxxxx
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/iio/adc/ingenic-adc.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/iio/adc/ingenic-adc.c
+++ b/drivers/iio/adc/ingenic-adc.c
@@ -71,7 +71,7 @@
 #define JZ4725B_ADC_BATTERY_HIGH_VREF_BITS	10
 #define JZ4740_ADC_BATTERY_HIGH_VREF		(7500 * 0.986)
 #define JZ4740_ADC_BATTERY_HIGH_VREF_BITS	12
-#define JZ4770_ADC_BATTERY_VREF			6600
+#define JZ4770_ADC_BATTERY_VREF			1200
 #define JZ4770_ADC_BATTERY_VREF_BITS		12
 
 #define JZ_ADC_IRQ_AUX			BIT(0)